Karen Johnson is a Senior Program Officer at the Bill & Melinda Gates Foundation. Karen's work centers around three areas of K-12 personalized learning: measuring product efficacy of edtech tools with the Learning Assembly, continually gauging and understanding what teachers need (Teachers Knows Best), and spurring development of edtech tools that meet the needs of teachers and students. Previously, Karen spent a decade marketing and building K-12 digital tools in social studies, science, math and language arts. She has spent countless hours conducting usability tests with teachers and working with software developers to implement teachers' feedback. Karen is currently exploring how edtech tools can better meet the needs of English Language Learners.